In 2015, the city of São Paulo, Brazil, began providing free public transportation to all secondary education students enrolled in public schools, benefiting nearly 1.5 million teenagers since its implementation. This study aims to evaluate the impacts of this policy, examining both short-term outcomes, such as secondary education enrollment, completion, proficiency, and concurrent participation in the formal labor market, as well as medium-term outcomes, including higher education enrollment, formal labor market participation, and wages after completing school. The analysis leverages a rich longitudinal dataset that tracks all Brazilian students through basic and higher education, as well as their participation in the formal labor market, from 2007 to 2023. To identify the policy’s impacts, we will implement a difference-in-differences strategy, comparing changes in outcomes for students in São Paulo after the policy’s adoption with changes observed for students in other Brazilian cities attending schools with similar pre-treatment characteristics. Additionally, we will examine heterogeneity in policy effects within São Paulo by comparing changes in outcomes between neighborhoods with higher and lower levels of public transportation accessibility. A preliminary analysis, based on this empirical strategy and using publicly available school-level data, estimated reductions in dropout rates of up to 3.4% in the first year of secondary education following the policy’s implementation. The individual-level analysis proposed in this registered report has already been approved and will be conducted in the Brazilian Ministry of Education’s Protected Data Room between August and September 2025.